I can imagine it did!
Are they not getting grief over the products being the same then (If they are exactly the same), or is it not widely known?
I don't think the old formulations were the same were they? C5 especially.
My understanding is that with the new forumulations they've isolated the core part of the product. Thus resulting in a loss of beading etc in C5, and the need for C1.5 to complete the C1. The C1.5 was in-built before
ie- Amatuers can't make cup cakes. But if you sell the sponge and the icing seperately its easier, albeit it wont look as good.
(thats just my take on things, correct me if I'm wrong)
One or two got a bit annoyed for some reason, it has been discussed quite a bit on DW. But TBH what difference does it make? The prices per ml worked out the same when buying the same amounts, so costs weren't different. You could have bought it from one of their retailers if you really wanted C1 when you couldn't get it from GT direct.
They never said they were different, just didn't offer it in a bottle for non pro's direct for use on paint, so in theory suggesting to you that you shouldn't use it on paint but not actually saying so.
I bought C4 and C5, used them separately on plastic and wheels, then bought C1. When I got another set of alloys I finished off the last of my C5, then finished off the last of my C4, then started on the C1. Old formula's of C1, 4 and 5 were all the same, as are the new formula's, albeit the new C1 is sold with C1.5 as the new formula has greatly reduced water behaviour. So you can still use the new C4 or C5 on paint or on wheels and plastics and top it up with C1.5.
By breaking the products down they believe they can get a better base product of hardness, application, etc but this lost the water behaviour, so released C1.5 to bring it back up to the standards of the old C1. So in theory they claim to have a combination of C1 + C1.5 that will outperform the old C1.
IMO though, I've found the water properties to not last all that long with C1.5 on bare paint compared to a quality wax or sealant. So I'm not sure on its properties when applied over the top of a nano sealant when in theory it should be difficult for things to bond to, albeit they are designed to work together but I'm a bit skeptable.
Gally's up to speed with the latest with his insider friend / detailer of the year so sur he can fill in with more detail